Sheet for loose-leaf book pages



y 8, 4 w. P. PITT SHEET FOR LOOSE-LEAF BOOK PAGES Filed March 1, 1944 A v Zhwento-r Patented May 8,

, UNITE D STATES PATENT o'rr cei SHEET FOR LOOSE-:LEA OOK PAGES t t y William rammar. Application March 1, 1944; Serial No.524,569

zQlaims. (c1. 129 1) This-invention relates topaper sheets for loose leafbook pages, which have perforations or holes therethrough spaced along the margins to receive the binding rings or pins of a binder. t

Frequently the paper sheets are too ,thin and weak or are roughly handled so that they become 'Worn or torn by frictional contact with the binder rings or studs at the edges of said binding perreeni'orce such sheets, against such wear and tear.

Heretofore, flat rings or stripsof cardboard or .fabric or metal have been applied to. the, sheets around the holes by being embedded in the sheets,

either by cutting away the sheetto receive the ring or strips, or bypressingthe flanges of metal.

eyelet into the paper so that the exposed surface of the reenforcing element is flush with the surface of the sheet, whereby to obviate bulgingof a pile of the sheet'salong the binding margin that would occur if i the reenforcements projected above the surfaces of the sheets. These structures are costlyand in-effect defeat their purpose, because the sheets must be thick enough to receive the embedded reenforcing element and the thicker thesheet the less the need for the reenforeement.

outoi' thesheet. t

Another proposal has been the superficial application adhesively to the sheet of metal foil reenforcing elements so thin that they do not increase substantially the combined thicknesses of th sheet and one of said elements is not substantially greater than the thickness of the sheet alone. This structure fails to completely solve the problem because it is limited to unusually Moreover, the eyelet is rigid and easily is torn accidentally to be torn pulled off the sheet.

Therefore a prime object of my invention is to provide a reenforced sheet of the general character described whichshall overcome the objection to and disadvantages of the knownqsheets, which shall be simple and inexpensive and shall reduce substantially the injury to said sheet from wear and tear at the binding holes.

Another object isto provide such a loose leaf book page wherein the reenforcing element shall be embedded in the paper sheet withoutcutting away of the sheet and without increasing the combined thickness of the sheet and the reenor distorted itself or to be forcing element.

Other objects are to provide a novel and improved method of applying a reenforcing element description in conjunction with forationsbMany attempts have been made to 1m binder sheet having a reenforcement ernbddy-.

element and reenforce itagainst distortion from bending; and to obtain other results and advantages that will bebrought out by the following ing drawing in which t t Figure 1 is a perspective view of a loose leaf ing the invention.

Figure 2 is an enlarged transverse vertical sectionalview through the sheet .on the line 22 of Figure l. t

Figur 3 isa fragmentary transverse vertical sectional viewthroughthe sheet, metal re'enforcethin sheets, and the reenforcing element is thin and is exposed at its edges which makes it liable ment and applying dies for securing the metal 1 reenforcement to the sheet.

i ure 4 ls a greatly enlarged fragmentary vertical sectional view through a portion of the sheet and a portion of the reenforcing element. Figure 5 is afragmentary sectional perspective view of a sheet embodyinga modified form of the invention, and

Figured is a fraginentaryperspective view of another modified form of sheet.

Specifically describing the embodiment of the invention illustrated in Figures 1 to 4 inclusive, the reference character A designates a sheet of the material to serve as a loose leaf binder sheet. It is desirable that the material of the sheet be fibrous and preferably it is paper. The thickness of the sheet may vary, but generally will be of the order of .004". As usual the sheet has a plurality of perforations or holes therethrough and spaced along one margin to receive the binding rings or pins of a loose leaf binder, and in accordance with the invention, each of the binding holes B is reenforced by a metalreentforcing element 0.

ment would be of a thicknessof about .0015".

The reenforcing element may be applied to the sheet in several different ways, but preferably a flat disc or wafer of sheet metal I is pressed into one side of the sheet, for example by the dies 1 2 and 3 as shownin Figure 3, with an adhesive or cement, such as a thermoplastic substance imth accompanyposed between the disc and the loose leaf sheet,

and so that the exposed surface of the disc is substantially flush with the surface of the fibrous sheet. During. this operation the fibers on the surface of the loose leaf sheet are broken and bent and some of the fibers are caused to lie along the edges of the disc, as indicated at 4 in Figure 4. At the same time, the fibers in the portions of the loose leaf sheet between the disc and the opposite side of the sheet are tightly compressed together as indicated at 5 more compactly than elsewhere in the sheet so that said portion of the sheet is strengthened. The adhesive is caused to run along the fibers and thereby firmly attach them to the surfaces of the'disc and the fibers at the same time, being embedded in the adhesive, serve as reenforcements therefor. The

adhesive will impregnate the'fibrous sheet'at the edge of the disc on the surface of the sheet and provide a substantially smooth and continuous surface between thesheet and the disc.

Thereafter the binder hole B may be. punched throughthe fibrous sheet A and the metal disc I at the same time. During this punchingoperation a burr 6 may be formed on the underside .of .the disc at the edge of the hole and the burr may be caused to penetrate the fibrous sheet andbecome attached to the fibers. .Where the disc is originally punched from the sheet, the outer edge of the underside of the disomay have a similar burr I which penetrates. the fibrous sheet and becomes attached to the fibers a the discis ap- Preferably the adhesive will be thermoplastic and will be heated during the pressingvof the disc into the fibrous sheet, and the adhesive has some elasticity to reduce the tendency of thefibrous sheet to pull away from the edges of. the disc or vice versa.

If desired, the fibrous sheetA may be punched first, after which the perforated metal reenforcement can be applied to the sheet; or the.binder hole and a recess to receive the reenforcing disc could be formed in the fibrous sheet after which the perforated reenforcing disc could be cemented in the recess. It will also be obvious to those skilled in the art that if desired the recess in the fibrous sheet may first be formed after which the unperforated disc I might be cemented in the recess. I

A modification of the invention is shown in Figure 5 where the reenforcing element D is a rectangular piece of metal that has a hole 8 in register with the binder hole 9 in the fibrous sheet E.

, In Figure 6 is shown a metal strip F extending along the margin of the fibrous sheet G andhav- :ing a plurality of perforations l0 therein registering with the binder holes II in the fibrous sheet G. I

Other modifications and changes in the details of construction of the loose leaf binder sheet and the manner of applying the reenforcing element will occur to those skilled in the art as within the spirit and scope of the invention. i

. What I claim is:

l. A loose-leaf binder sheet having a binder hole and a recess in one side bordering said hole that has been formed by pressing the material of said sheet, and a flat metal foil reenforcing element cemented in said recess with its exposed surface flush with the surface of said sheet and having a burr at its edgespenetrating said sheet and attached to the fibers thereof.

2. A fibrous loose leaf binder sheet having a binder hole and a recess in one side bordering said l1ole,'the fibers in the portion of said sheet between the bottom of said recess and the other side of said sheet being compressed together more compactly than elsewhere in the sheet whereby said portion of the sheet is strengthened, a flat metal foil reenforcement seated in said recess with its exposed surface flush with thesurface of said sheet, and an adhesive betweensaid element and the walls of said recess, a plurality of fibers projecting from the walls of said recess and running along the edges of said element so that said fibers are firmly secured to saidelementand said adhesive is reenforced by said fibers extending therethrough.

. WILLIAM P. PI'I'I. 

